Ochrolechia

a genus of lichens of the family Lecanoraceae. The lichens have scaly, crusty, grayish or yellow thallus. The spores are single-celled, colorless, and large. Of the approximately 30 species, more than 20 are found in the USSR, primarily in the north. The lichens thrive on mosses, soil, mossy crags, rocks, and tree bark. The cudbear (O. tartarea) and similar species contain dyes.